1. cell membrane
2. cytoplasm
3. ribosomes
4. chromosomes (usually 1)

1. cell wall
2. glycocalyx

1. flagella
2. pili
3. fimbrae
4. capsules
5. slime layers
6. inclusions
7. actin cytoskeleton
8. endospores

1. filament (long part)

2. hook

3. Basal body (anchors to cell)

1. Monotrichous (1 flagellum)
2. Amphitrichous (two flagella, one on each end of cell)
3. Lophotrichous (Many flagella on ONE END of cell)
4. Peritichous (Many falgella all over cell)

flagellated bacteria move in response to chemical signals

• positive chemotaxis- toward direction of favorable stimulus (nutrients)
• negative chemotaxis- away from repellent compound (harmful)

Runs and tumbles

Runs are longer going up gradient

Tumbles to test environment

• axial filaments aka periplasmic flagella
• enclosed in space between the cell wall and the cell membrane
• give corkscrew or wriggly motion

• elongated, rigid tubular structures made of the protein pilin
• used in conjugation- partial transfer of DNA from one cell to another

Pili are found on in gram-positive bacteria

True or False

Fimbriae are small, bristlelike fibers found on the surface of a bacterial cell and most of them contain protein.

They stick to each other and to surfaces, causing colonization

Outside the cell envelope

Made of repeating polysaccharide units, protein, or both

Protects the cell

Helps the cell adhere to the environment

Protects the cell against phagocytes (biofilm)

1. When the glycocalyx is loosely shielding the bacteria

2. It protects the bacteria from loss of water and nutrients; also adherance

1. When the glycocalyx is bound more tightly to the cell and is denser and thicker

2. Protects from phagocytosis

• Gram + has two layers: cell wall (thick) and cytoplasmic membrane--- also contains teichoic acid and lipoteichoic acid
• Gram - has three layers: outer membrane, cell wall (thin), and cytoplasmic membrane--- also has perplasmic space surrounding the cell wall

What is the cell wall made of?

What does it keep the cell from doing?

What medical technology targets the cell wall?

peptidoglycan

keeps cell from rupturing because of changes in pressure due to osmosis

Antibiotics target the cell wall, giving it little protection from lysis

Uppermost layer contains lipopolysaccharides (LPS)

Innermost layer made of phospholipid layer-- anchored to cell wall

1. Mycobacterium (have mycolic acids- fatty acid chain giving high degree of resistance; basis for acid-fast staining)
2. Archae (unusual and chemically distinct)
3. Mycoplasmas (no cell wall)

Mycoplasmas are very small and range in shape and can be found in many habitats.

Its cell membrane is stabilized by sterols and is resistant to lysis.

*Important medical species: Mycoplasma pneumonia (aka walking pneumonia)

L-form arise naturally from a mutation in the wall-forming genes. They have no distinct shape.

Gram + are called protoplast

Gram - are called spheroplast

• Contains primarily phospholipids and proteins

Provides site for functions such as energy reactions, nutrient processing, and synthesis

Regulates transport

Secretion

What is a bacterial chromosome?

Where is it located?

What's its method of replication called?

• single circular strand of DNA
• aggregated in a dense area called the nucleoid
• replicates through binary fission (more rapid than human DNA because happens all at once)

• Nonessential pieces of DNA forming in double-stranded circles
• Have protective traits (drug resistance or production of toxins)
• Can pass between bacteria via pili or phages

70S

Humans have 80S

Serve as storehouse of nutrients

(bacteria lay down nutrients in them during periods of nutrient abundance; use when nutrients are depleted)

Contributes to cell shape

Arranged in helical ribbons around cell just under cell membrane

1. vegatative (metabolically active and growing)
2. endospore (metabolically inactive)

Bacillus

Clostridium

Sporosarcina

All Gram +

1. coccus (spherical)
2. Bacillus (rod)
3. Spirillum (spiral)

Coccobacillus= short and plump

Vibrio= gently curved bacillus

Gram-negative

Alternate between mammals and blood-sucking anthropods

Cannot survive or multiply outside host cell

Cannot carry out metabolism completely on their own

Examples: Rocky Mountain Spotted Fever (Rickettsia rickettsii) and endemic typhus (Rickettsia typhi)

require host cells for growth and metabolism

Not closely related

Not transmitted by arthropods

Examples: Chlamydia trachomatis (STD) and Chlamydophilia pneumonia (lung infections)

Some produce oxygen during photosynthesis

Give us most of the oxygen we have today

AKA Blue-Green Bacteria

Contain chlorophyll and have gas filled inclusions which allow them to float on water

What are Green and Purple Sulfur Bacteria?

 Where do they live?

Photosynthetic but don't give off oxygen

Live in sulfur springs, freshwater lakes, and swamps

What makes Archaea distinct?

What types of environments can they live in?

Type of prokaryotes that have been around the longest-- they have adapted to every environment

They love extreme environments including extreme heat/cold, salt, acid, pH, pressure, and atmospheres